69 Camaro caliper slide pin/rod originality question

[KevinW]

Happy New Year for 2023!

I have been working on restoring my original brake system components and am at the front calipers now. I have restored/rebuilt one and was testing the caliper slide pins (pad retaining rod) and found an issue.

I replaced the little O-rings and the pin does not go through the outside O-ring. I purchased Right stuff pins CB6901 a long time ago and thought these were not the correct part.

I looked it up on Right stuff website: https://rpui.com/-Repair-Parts-1969-GM-A-Body-Single-Piston-Front-Caliper-Pin-Each-CB6901 and sure enough this part is only listed for GM-A body cars. And web page says it does not fit a 1969 Camaro. :(

So I pulled out one of my originals and though they are the same diameter, the length and thread area is a little different. Original is 4 1/8" long, while new pin is 4 3/8" long.

So then I looked at Heartbeat and their pin (rod) looks the same as the Right Stuff pin, but the description says it fits all GM single bore calipers including 69 Camaros: https://www.heartbeatcitycamaro.com/12230/1969-1981-Camaro-%26-Firebird-Front-Disc-Brake-Pad-Retaining-Rod-Bolt-Each/

When I do a Google image search all the pins I see are this longer style and most say it fits all the GM models.

So will this longer pin work properly in 69 Camaros?

Or is there a more accurate pin that matches the 69 version?

And how free are the calipers supposed to slide on the pins? I think I need to grease them.

I have found only 3 original pins, so I have to dig more and see if I can find more and see if any are restorable. thx

[Lynn]

They need to be free. Yes, there is a caliper grease that needs to be judiciously applied on both the pins and the outer surface of those sleeves that the pins go through. I always used a pocket screwdriver and put grease on the rubber bushings before sliding in the pins and sleeves.

[AnthonyS]

Morning and Happy New Year, I agree with Lynn, they must slide along the pins or you'll get uneven wear on the pads and rotors from just the action of the piston side rather than an equal wear pattern from both sides. As to diameter of the caliper bolts, that's more critical than their overall length IMHO (if they're a tad too long that's fine as long as they don't interfere with the rim) which is doubtful as they'd need to be quite long for that. Too short is more of an issue obviously. Original GM bolts / pins are typically stamped "S" and sometimes I've seen "L" - I would think they are reusable if they show no damage and still have good threads; they're not really a stress item.

The caliper should slide freely, but not necessarily by hand, just with the braking action of the car. Lube the rubber o-rings and then periodically check for even wear once you're driving - often the piston side pad wears more quickly due to an uneven pressure from the whole caliper not sliding.

I likely have some original pins if you decide to go that way - may even have a single if you PM me with what you want to match up too. Check for the vendor stamp "S" and take a measurement of overall length you want to match; I'm sure there was variance between vendors. The "S" stamp is often in the hex head on the "outside" of the bolt when installed, but they can be on the inboard side too.

Cheers and good luck with the project!
Anthony

[KevinW]

Thanks Lynn and Anthony!

After thinking about it, I realized I needed grease (actually shop manual says silicone spray)

So I got out the parts and did a trial assembly and worked the pins in. After a couple presses and the silicone spray they are much freer now.

My original pins are "S" and the repro ones are "L" both stamped on the small end.

Here is the assembly, seems to all fit fine. Yes, the repro bolts are a bit longer than originals, but since mine will be driven I can use these. :)

[KevinW]

Morning and Happy New Year,

I likely have some original pins if you decide to go that way - may even have a single if you PM me with what you want to match up too. Check for the vendor stamp "S" and take a measurement of overall length you want to match; I'm sure there was variance between vendors. The "S" stamp is often in the hex head on the "outside" of the bolt when installed, but they can be on the inboard side too.

Anthony

Thanks Anthony. I went on a hunt and found 5 more, so I have 8 to clean and see if I have a usable set to keep my options open. :)

[AnthonyS]

Kool and the Gang! Looking good!